Chapter 3. Configuring Fencing with Conga

This chapter describes how to configure fencing in Red Hat High Availability Add-On using Conga.

Note

Conga is a graphical user interface that you can use to administer the Red Hat High Availability Add-On. Note, however, that in order to use this interface effectively you need to have a good and clear understanding of the underlying concepts. Learning about cluster configuration by exploring the available features in the user interface is not recommended, as it may result in a system that is not robust enough to keep all services running when components fail.

3.1. Configuring Fence Daemon Properties

Clicking on the Fence Daemon tab displays the Fence Daemon Properties page, which provides an interface for configuring Post Fail Delay and Post Join Delay. The values you configure for these parameters are general fencing properties for the cluster. To configure specific fence devices for the nodes of the cluster, use the Fence Devices menu item of the cluster display, as described in Section 3.2, “Configuring Fence Devices”.
  • The Post Fail Delay parameter is the number of seconds the fence daemon (fenced) waits before fencing a node (a member of the fence domain) after the node has failed. The Post Fail Delay default value is 0. Its value may be varied to suit cluster and network performance.
  • The Post Join Delay parameter is the number of seconds the fence daemon (fenced) waits before fencing a node after the node joins the fence domain. The Post Join Delay default value is 6. A typical setting for Post Join Delay is between 20 and 30 seconds, but can vary according to cluster and network performance.
Enter the values required and click Apply for changes to take effect.

Note

For more information about Post Join Delay and Post Fail Delay, see the fenced(8) man page.